Video: Audi A6 and Infiniti M35 crash tests

You paid a lot for your luxury car, but if you get into an accident, was that car worth the money in terms of safety?

For most people, driving through an intersection or cruising down the road as cars whiz by on the other side of that yellow line is so routine they rarely give it a second thought. But that routine can turn tragic in just an instant.

“The two main collision types producing deaths and serious injuries are front and side crashes,” says Brian O’Neill of the Insurance Institute for Highway Safety, a non profit group funded by insurance companies looking to improve vehicle safety and reduce claims. The group designed two very demanding front and side crash tests.

A pair of luxury cars— the $49,000 2005 Audi A6, and the $40,000 2006 Infiniti M35— meet federal safety standards like all cars. Now both are offering new designs, and the manufacturers’ commissioned the institute to put them to its test.

Front crash test The Infiniti M35 simulates what might happen if two cars of the same weight, traveling at 40 miles per hour, crash into each other off center.

"The crumple zone has done its job because the compartment, which is strong, has resisted intrusion. In fact, there’s virtually no intrusion inside this compartment.So this was an exemplary performer," says O'Neill.

For the Audi A6, although the driver dummy records forces that could cause a minor leg injury, O’Neill says it’s not serious, soit too is rated “good” and a “Best Pick.”

But, the much tougher test was ahead. What might happen if an SUV were to slam into the side of a car at 31 miles per hour?

Side crash test
The higher front end of the SUV puts your head at risk, and according to O’Neill, and head injuries account for about half the deaths in serious side impact crashes.

According to O'Neill says a car can’t pass his side test unless it has a good structure and side airbags that protect the head.

Unlike most cars, in the Infiniti M35, those airbags are standard equipment. Although the head gets good protection, O’Neill says the side of the Infiniti collapses a little too much.

"There’s a possibility that a person might get some rib injuries in the crash," says O'Neill. "It’s still a good performer, but it doesn’t quite make a 'Best Pick.'"

So the M35, which is a “Best Pick” in the frontal test, gets a “good” rating in the side test.

For the Audi A6, the institute finds it has a good structure. Side airbags are standard equipment as well.

"The injury measures on the driver dummy were good. The injury measures on the rear dummy were also good," says O'Neill. "That’s because this curtain protected the head of both dummies— and this bag here protected the torso body region."

The Audi A6 is one of the very few cars the institute calls a “Double Best Pick.” It gets a “good” and a “Best Pick” in both the side and the front test.

These cars are the beginning of what O’Neill hopes is a new generation of vehicles that does well in his test hall and in the real world.

"We’re gonna see good performers across the board, I think, as all of the vehicles get redesigned. That will be in the next few years," he says.

Dateline wires the home of a volunteer, Jenny, from top to bottom with hidden cameras. Then she called repairmen to her house for a simple problem we created as a test with Jenny's pool. NBC's Chris Hansen reports.